155217216 has 112 divisors (see below), whose sum is σ = 512064000. Its totient is φ = 40312320.

The previous prime is 155217211. The next prime is 155217247. The reversal of 155217216 is 612712551.

It is a tau number, because it is divible by the number of its divisors (112).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155217211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9535 + ... + 20033.

It is an arithmetic number, because the mean of its divisors is an integer number (4572000).

Almost surely, 2^155217216 is an apocalyptic number.

155217216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155217216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (256032000).

155217216 is an abundant number, since it is smaller than the sum of its proper divisors (356846784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155217216 is a wasteful number, since it uses less digits than its factorization.

155217216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10532 (or 10522 counting only the distinct ones).

The product of its digits is 4200, while the sum is 30.

The square root of 155217216 is about 12458.6201483150. The cubic root of 155217216 is about 537.4193465426.

Adding to 155217216 its reverse (612712551), we get a palindrome (767929767).

The spelling of 155217216 in words is "one hundred fifty-five million, two hundred seventeen thousand, two hundred sixteen".